I remember finding this way back in 2002, after making my own "Quick and Dirty Preview of Solid State Physics". I had to make this site for a seminar class. Basically each student had to present on some general physics topic and then make a webpage for it.
http://www.pha.jhu.edu/~jeffwass/2ndYrSem/slide1.html
Made me realise after coming across the Britney Spears page, the brilliance of basing a potentially dry academic presentation around a pop culture celebrity.
Eg, another pop cultural site/meme around that time was MC Hawking (E=MC). Some guy made gangsta rap tunes using a voice synthesiser similar to Stephen Hawking's, with loose physics references.
Btw - in my seminar class, the best presentation (maybe the only one I remember) was by one dude (now a professional astronomer) who interspersed graphs of cosmic inflation with pictures of an inflatable sheep sex doll. The prof wasn't too pleased. Not sure where that webpage is nowadays...
The most recent instance I've seen of this pop culture/dry theory combo was in the movie The Big Short.
They have Margot Robbie (Australian supermodel) sip champagne in a bubble bath while explaining the dynamics of the derivatives market and how it created a bubble in 2008. There's also a scene where Anthony Bourdain (celebrity chef) is prepping food in a kitchen and talking about fish stew as a metaphor for securitization and CDO's.
I find that the best teachers have such a complete mastery of a subject that they can almost perfectly translate it into a common language (pop culture) to make it more relatable and entertaining. They let inquisitive students probe deeper, past the metaphor. The worst teachers usually keep things as academic and dry as possible as a shield against understanding, which leads to questioning, which might call the teacher's knowledge into question or derail the class.
The entire "Good Eats" series on the food network with Alton Brown? Light food biochemistry combined with entertaining pop culture references?
The network is pretty boring now, focusing mostly on extremely shiny and polished aspirational personalities and the usual "reality" game shows, but in the old days the network used to be about food...
The style of music you're referring to is called Nerd Core. I had a friend who was really into it and he took me to a show about ten years ago. Lyrics ranged from video games to math and physics with clever word play and a lot of "in" jokes targeted at the intended audience. I had fun and could see why my buddy enjoyed it so much.
It was different and enjoyable hearing someone rap with terms nerds would recognize. Now, we just need someone with the talent of a big-name, pop singer doing it. :)
I feel sad that the CV of this obviously talented physicist shows that he has spent the last 8 years working in search engine optimization for e-commerce websites. I wonder if society would not have benefited more if someone without a physics PhD took his job and he took one involving physics.
It was all borrowed from http://www.routergod.com. They had Britney doing OSPF, Christina Aguilera on BGP, Mulder and Scully on IOS basics. All in Character. Whoever writes Securitay is probably an old BSD nerd.
In 1900, 3 years after JJ Thomson discovered the electron, physicist P. Drude came up with a simple approach for modelling metals. He assumed electrons would scatter off the atomic ions, all behaving classically like balls. Even this incredibly simplistic model, which ignores the important effects of both the quantum nature of electrons, and the crystalline lattice ordering of atoms in a metal, can predict Ohm's Law. Ie, that current density is proportional to the applied electric field.
https://en.m.wikipedia.org/wiki/Drude_model
That's probably the simplest explanation, and adding in more accurate assumptions to the model still shows that Ohm's Law still follows in the classical regime.
Though clearly the band gap (which involves insulators and semiconductors) has important effects when you look at the the impact of the atomic lattice on quantum states. And the 2nd-order electron-lattice-electron interaction that allows Cooper pairing and superconductivity.
You can also get strange things in nanoscale systems, such as non-Ohmic ballistic electronic current, where resistance is only due to the contacts of a device but not the length.
How does electric current through a (non-super-) conductor convert energy to heat?
You have a coupling to other, non-electron/hole degrees of freedom in the system. The stronger that coupling is, the easier it is to transfer energy between the systems and the worse your conductor tends to be.
As much as I know about the subject, I like this answer more than all others here. The "bumping" interpretations don't appear to match what we know about the atoms and the particles for many decades and look to me like an explanation for small kids.
One says electrons bump into electrons, the other says electrons bump into non-charge-carriers. Someone on Twitter said it was phonons.
I guess I can kind of imagine a pachinko machine, but this is all very unsatisfying. :-)
Edit: From the Wikipedia link: "Charged particles in an electric circuit are accelerated by an electric field but give up some of their kinetic energy each time they collide with an ion"
I mean, electrons are very very lightweight and tend to move quite slowly for typical currents. How much kinetic energy can they give?
> "I mean, electrons are very very lightweight and tend to move quite slowly for typical currents. How much kinetic energy can they give?"
I only have a layman's understanding of this whole process, so I could be missing some important details, but I believe it's necessary to look at the atoms as a whole rather than just the electrons...
Consider, the electrons (from the outermost orbit of the nucleus) are travelling from atom to atom (the ease by which they can come and go determines how conductive the material is).
During this process, when an atom has more electrons than its stable state it is negatively charged, and when it has less electrons than its stable state it is positively charged. The greater the polarisation between the positively-charged atoms and the negatively-charged atoms, the more electrons can move through the material. I believe the potential difference between the poles is voltage, and the volume of electrons flowing at a given time is current, but I could be wrong on that.
If electrons lost their momentum and energy only to other electrons, then in aggregate, electrons would keep their momentum and energy. Since electrons do not permanently keep their momentum and energy in normal conductors, they therefore must lose momentum and energy to non-electrons.
Also, if you look at the Wikipedia link on the comment that says claims electrons lose energy to electrons, you'll see that Wikipedia says electrons lose energy to ions, not electrons.
(Also, as a condensed matter physicist, I always feel a little dirty/inaccurate saying that electrons carry charge currents. I prefer the vaguer charge carrier, because charge carrier can refer to an ensemble of electrons.)
Then there is Danica McKellar from The Wonder Years, who really did get a degree in mathematics, and has written several books on the subject for young girls.
Ha, I am surprised to see that page on HN.
I remember finding this way back in 2002, after making my own "Quick and Dirty Preview of Solid State Physics". I had to make this site for a seminar class. Basically each student had to present on some general physics topic and then make a webpage for it. http://www.pha.jhu.edu/~jeffwass/2ndYrSem/slide1.html
Made me realise after coming across the Britney Spears page, the brilliance of basing a potentially dry academic presentation around a pop culture celebrity.
Eg, another pop cultural site/meme around that time was MC Hawking (E=MC). Some guy made gangsta rap tunes using a voice synthesiser similar to Stephen Hawking's, with loose physics references.
Btw - in my seminar class, the best presentation (maybe the only one I remember) was by one dude (now a professional astronomer) who interspersed graphs of cosmic inflation with pictures of an inflatable sheep sex doll. The prof wasn't too pleased. Not sure where that webpage is nowadays...
The most recent instance I've seen of this pop culture/dry theory combo was in the movie The Big Short.
They have Margot Robbie (Australian supermodel) sip champagne in a bubble bath while explaining the dynamics of the derivatives market and how it created a bubble in 2008. There's also a scene where Anthony Bourdain (celebrity chef) is prepping food in a kitchen and talking about fish stew as a metaphor for securitization and CDO's.
I find that the best teachers have such a complete mastery of a subject that they can almost perfectly translate it into a common language (pop culture) to make it more relatable and entertaining. They let inquisitive students probe deeper, past the metaphor. The worst teachers usually keep things as academic and dry as possible as a shield against understanding, which leads to questioning, which might call the teacher's knowledge into question or derail the class.
The entire "Good Eats" series on the food network with Alton Brown? Light food biochemistry combined with entertaining pop culture references?
The network is pretty boring now, focusing mostly on extremely shiny and polished aspirational personalities and the usual "reality" game shows, but in the old days the network used to be about food...
1 reply →
The style of music you're referring to is called Nerd Core. I had a friend who was really into it and he took me to a show about ten years ago. Lyrics ranged from video games to math and physics with clever word play and a lot of "in" jokes targeted at the intended audience. I had fun and could see why my buddy enjoyed it so much.
A few sent some of those to me. Here's one that's not so bad that describes many [criminal] hackers' lives from start to rough parts to reform.
http://www.youtube.com/watch?v=Am9Ctf20nS0
It was different and enjoyable hearing someone rap with terms nerds would recognize. Now, we just need someone with the talent of a big-name, pop singer doing it. :)
https://www.youtube.com/watch?v=4nigRT2KmCE
Of course, that describes regular rap music pretty well too, but somehow that was just never officially nerdy enough.
> MC Hawking
https://www.youtube.com/watch?v=jJ5zOOnGOjE
Doesn't get more gangsta than that. it even has the squealy signature Crip notes.
I feel sad that the CV of this obviously talented physicist shows that he has spent the last 8 years working in search engine optimization for e-commerce websites. I wonder if society would not have benefited more if someone without a physics PhD took his job and he took one involving physics.
First we would have to find a research job which paid as well as SEO jobs do.
Academic jobs have a lot more going against them than just the pay tho.
1 reply →
You mean, Swift on Security wasn't an original idea?
It was all borrowed from http://www.routergod.com. They had Britney doing OSPF, Christina Aguilera on BGP, Mulder and Scully on IOS basics. All in Character. Whoever writes Securitay is probably an old BSD nerd.
Oh sure, you can find explanations of good conductors and semiconductors all over the web.
But what I have never found is an explanation of poor conductors: How does electric current through a (non-super-) conductor convert energy to heat?
Do you mean "why is there resistance"?
In 1900, 3 years after JJ Thomson discovered the electron, physicist P. Drude came up with a simple approach for modelling metals. He assumed electrons would scatter off the atomic ions, all behaving classically like balls. Even this incredibly simplistic model, which ignores the important effects of both the quantum nature of electrons, and the crystalline lattice ordering of atoms in a metal, can predict Ohm's Law. Ie, that current density is proportional to the applied electric field. https://en.m.wikipedia.org/wiki/Drude_model
That's probably the simplest explanation, and adding in more accurate assumptions to the model still shows that Ohm's Law still follows in the classical regime.
Though clearly the band gap (which involves insulators and semiconductors) has important effects when you look at the the impact of the atomic lattice on quantum states. And the 2nd-order electron-lattice-electron interaction that allows Cooper pairing and superconductivity.
You can also get strange things in nanoscale systems, such as non-Ohmic ballistic electronic current, where resistance is only due to the contacts of a device but not the length.
How does electric current through a (non-super-) conductor convert energy to heat?
You have a coupling to other, non-electron/hole degrees of freedom in the system. The stronger that coupling is, the easier it is to transfer energy between the systems and the worse your conductor tends to be.
As much as I know about the subject, I like this answer more than all others here. The "bumping" interpretations don't appear to match what we know about the atoms and the particles for many decades and look to me like an explanation for small kids.
These are two great responses, but they seem to be saying opposite things.
https://news.ycombinator.com/item?id=10877121
One says electrons bump into electrons, the other says electrons bump into non-charge-carriers. Someone on Twitter said it was phonons.
I guess I can kind of imagine a pachinko machine, but this is all very unsatisfying. :-)
Edit: From the Wikipedia link: "Charged particles in an electric circuit are accelerated by an electric field but give up some of their kinetic energy each time they collide with an ion"
I mean, electrons are very very lightweight and tend to move quite slowly for typical currents. How much kinetic energy can they give?
> "I mean, electrons are very very lightweight and tend to move quite slowly for typical currents. How much kinetic energy can they give?"
I only have a layman's understanding of this whole process, so I could be missing some important details, but I believe it's necessary to look at the atoms as a whole rather than just the electrons...
Consider, the electrons (from the outermost orbit of the nucleus) are travelling from atom to atom (the ease by which they can come and go determines how conductive the material is).
During this process, when an atom has more electrons than its stable state it is negatively charged, and when it has less electrons than its stable state it is positively charged. The greater the polarisation between the positively-charged atoms and the negatively-charged atoms, the more electrons can move through the material. I believe the potential difference between the poles is voltage, and the volume of electrons flowing at a given time is current, but I could be wrong on that.
Electrons lose their energy to other things.
Here's one quick explanation why:
If electrons lost their momentum and energy only to other electrons, then in aggregate, electrons would keep their momentum and energy. Since electrons do not permanently keep their momentum and energy in normal conductors, they therefore must lose momentum and energy to non-electrons.
Also, if you look at the Wikipedia link on the comment that says claims electrons lose energy to electrons, you'll see that Wikipedia says electrons lose energy to ions, not electrons.
(Also, as a condensed matter physicist, I always feel a little dirty/inaccurate saying that electrons carry charge currents. I prefer the vaguer charge carrier, because charge carrier can refer to an ensemble of electrons.)
https://en.wikipedia.org/wiki/Joule_heating#Microscopic_desc...
Basically, physical movement of electrons involved in the current flow is hindered by other electrons.
Then there is Danica McKellar from The Wonder Years, who really did get a degree in mathematics, and has written several books on the subject for young girls.
I was wondering "who the heck is the Britney Spear person", but submitter just put the apostrophe in the wrong place.
This was one of the more helpful resources I found in 2001/2002 when I was taking semiconductor physics.
Same here. Same years even. I remember having a laugh and then realising it actually isn't made up gibberish.
For a second I thought I was going to hear auto-tuned voice-overs of Britney songs replaced with Semiconductor Physics lyrics.
I was disappointed. You have room to grow, britneyspears.ac.
lol this is an old one. I remember my advisor who was then a postdoc recommending it to me five years ago.
*Spears'
> *Spears'
No. Spears's